Skateboard riding has become an increasing popular pastime, especially among school age children. Such an activity provides a means of transportation and outdoor exercise.
Conventional skateboards consist of an elongated deck (as made of wood or fiberglass) with two truck and wheel assemblies mounted under the deck roughly shoulder width apart. The wheels are typically polyurethane and are mounted on an axle of a pivoting truck assembly. The truck includes a resilient ring that allows the truck to pivot about its connection with the deck, allowing the skateboard to tilt slightly over the wheels. This tilting causes radial displacement of the axles, allowing the board to turn. Decks range in width from 6 to 12 inches and from 2 to 3 feet in length. Much longer oversized boards, known as long-boards, are also used.
The size and weight of skateboards presents certain disadvantages. When not in use the boards most often are hand carried. In public commercial establishments, such as convenience stores and movie theaters, skateboards present difficulties for their user. The skateboard presents a hazard of knocking items off surfaces or bumping customers if the user is not careful. In addition if the user places the skateboard in an isle or other walkway, the board is a danger to other customers. In addition, the board is difficult to transport and store when not in use. For example on busses or trains, the user must ride carrying the skateboard or with the skateboard in the user's lap. Conventional skateboards are quite sizable and do not fit in a standard backpack and are difficult to fit into a school locker.
A number of different attempts have been made to provide a skateboard that is more portable. U.S. Pat. No. 5,505,474 to Yeh discloses a folding skateboard having a plurality of frame bars connected by a series of links. At a front and rear end of the frame bars are rotatable connectors onto which a wheel assembly is mounted. The rider stands on a platform mounted on the connector over the wheel assembly. A number of pins are used to hold the frame bars in position. The pins may be removed to fold the bars of the skateboard.
U.S. Pat. No. 5,769,438 discloses a skateboard having a front, middle and rear sections. A hinge joins the front section to the middle section and a second hinge joins the middle section to the rear section. Wheel assemblies are attached to the front and rear sections of the skateboard. The two hinges allow folding of the board, making the board more compact.
U.S. Pat. No. 5,971,406 discloses a foot supporting skate device. This device includes a skate, such as an inline skate, worn on a first foot. The skate includes a platform extending from the rear of the skate and having an additional wheel. A rider may position a second foot on this platform so that the skate may be used alone. The second foot could be used to propel the rider, as would be done with a skateboard.
U.S. Pat. No. 6,131,931 to Globerson et al. discloses a folding skateboard having front and back wheel and truck assemblies. The deck of the skateboard includes three sections. A first section is about half the length the board, and middle section having a width that is about the height of the wheel and truck assembly and the third section making up the remaining length of the skateboard. The sections are connected by hinges such that the board may be folded. In the folded position, the wheels are aligned side by side. This allows the board to compact to a size about half the size of the extended board, and one deck thickness greater in depth than an assembled board. Clips or fastening rods may be used to secure the board when it is in the open position.
U.S. Pat. App. Pub. 2003/0127816 A1 to Schnuckle at al. discloses a foldable skateboard. This device includes a pair of front wheels on an articulated strut attached to a central platform. A pair of rear wheels on a hinged support is also attached to the central platform. Over the back wheels is a small platform. The front and back wheels each may be folded over the central platform. A user would ride this device with one foot on the central platform. The other foot either provides the driving force for the skateboard or rests on the rear platform. The rear platform is directly behind the central platform requiring a user to position both feet along the longitudinal median of the device. This is also true of the rollerskate of U.S. Pat. No. 5,971,406. The central platform is at least as large as the rider's foot. The foot platform is in the same plane as the front and rear wheel axles.
To ride a conventional skateboard, a rider paces a front foot on the board at an angle (such as a 45 degree angle) relative to the longitudinal median axis of the board. Thus the toe area of the rider's foot is closer to one side of the board and the rider's heel is closer to the other side of the board. The second foot of the rider is used to propel the board forward. The “pumping” action of the foot provides a forward force to roll the skateboard forward. When the board coasts, the pumping foot is placed on the rear of the board, also at a angle similar to the angle of the front foot. To steer the board, toe or heel pressure is exerted to one side of the board. This angles the wheel axles on the truck, angling the wheels and turning the skateboard.
In the prior art, the foldable skateboards disclosed are all, when folded into the compact size, at least the size of the rider's foot, and in most cases are substantially larger. Most of the foldable or collapsible skateboards require an unconventional foot position. For example, U.S. Pat. No. 5,941,406 and U.S. Pat. Appln. Pub. No. 2003/0127816 A1 require a foot position in which the planted foot faces forward and the pumping foot is directly behind the planted foot when resting on the device. This is not the natural foot position when riding a conventional skateboard, and this foot position negatively impacts rider comfort and skateboard maneuver ability.